Radiant electric heaters are well known for use behind glass-ceramic cooking surfaces. Such heaters can comprise a dish-like support having therein a base layer of insulation material, such as microporous thermal and electrical insulation material. At least one electrical heating element is provided, supported on the surface of the base layer. One form of heating element which has found wide acceptance is an elongate electrically conductive ribbon which is supported on edge and partially embedded in the surface of the base layer.